Hemispherical differences in the shape and topography of asteroid (101955) Bennu

We investigate the shape of near-Earth asteroid (101955) Bennu by constructing a high-resolution (20 cm) global digital terrain model from laser altimeter data. By modeling the northern and southern hemispheres separately, we find that longitudinal ridges previously identified in the north extend into the south but are obscured there by surface material. In the south, more numerous large boulders effectively retain surface materials and imply a higher average strength at depth to support them. The north has fewer large boulders and more evidence of boulder dynamics (toppling and downslope movement) and surface flow. These factors result in Bennu's southern hemisphere being rounder and smoother, whereas its northern hemisphere has higher slopes and a less regular shape. We infer an originally asymmetric distribution of large boulders followed by a partial disruption, leading to wedge formation in Bennu's history.

Direct-acting antiviral treatment against hepatitis C virus infection in HIV-Infected patients - "En route for eradication"?

OBJECTIVES

Direct-Acting Antivirals (DAAs) opened a new era in HCV treatment. We report the impact of HCV treatment in French HIV-HCV coinfected patients.

METHODS

All HIV-HCV patients from the Dat'AIDS cohort followed between 2012 and 2015 were included. HCV status was defined yearly as naive, spontaneous cure, sustained virological response (SVR12), failure or reinfection.

RESULTS

Among 32,945 HIV-infected patients, 15.2% were positive for anti-HCV antibodies. From 2012 to 2015, HCV incidence rate increased from 0.35%PY to 0.69%PY in MSM, while median incidence was 0.08%PY in other patients. Median reinfection rate was 2.56%PY in MSM and 0.22%PY in other patients. HCV treatment initiation rate rose from 8.2% in 2012 to 29.6% (48.0% in pre-treated patients vs 22.6% in naïve patients). SVR12 rate increased from 68.7% to 95.2%. By the end of 2015, 62.7% of the patients were cured either spontaneously or following SVR.

CONCLUSIONS

HCV treatment dramatically increased in HIV-HCV patients in France from 2012 to 2015 resulting in HCV cure in nearly two-thirds of the patients in this cohort. Combined with a declining HCV prevalence, the prevalence of active HCV infection among HIV patients will drastically decrease in the forthcoming years.

Monitoring CD27+ memory B-cells in neuromyelitis optica spectrum disorders patients treated with rituximab: Results from a bicentric study

BACKGROUND

Rituximab (RTX) is increasingly used in the treatment of neuromyelitis optica spectrum disorder (NMO-SD). Administration regimen is not consensual as there is no reliable biomarker of RTX efficacy. In most cases, after induction, RTX is administered systematically every 6months.

OBJECTIVE

To assess efficacy and safety of a maintenance regimen based on CD19+ CD27+ memory B-cell (mBc) detection.

METHODS

We conducted a study in two French centers, including patients with NMO-SD who received an induction therapy with RTX. We compared the number of administered infusions, relapses and EDSS depending on two maintenance schemes (S1: administration of 1g RTX infusion every 6months or S2: a scheme based on regular mBc detection. 1g RTX was administered if mBc was >0.05%) RESULTS: 40 patients were included (mean age: 40.2years, F/M sex ratio: 5/1). Aquaporin-4 antibodies were positive in 75% patients. Under S1 regimen, all patients received 2 infusions per year, whereas under S2, they received 1.62 infusion per year. The mean interval between infusions under S2 was 7.4months, without decrease of clinical efficacy.

CONCLUSION

In our study, mBc-based administration of RTX allowed personalizing treatment administration and in several cases to lower the cumulative dose without loss of efficacy.

Hollow viscus injury due to blunt trauma: A review

Blunt abdominal trauma results in injury to the bowel and mesenteries in 3-5% of cases. The injuries are polymorphic including hematoma, seromuscular tear, perforation, and ischemia. They preferentially involve the small bowel and may result in bleeding and/or peritonitis. An urgent laparotomy is necessary if there is evidence of active bleeding or peritonitis at the initial examination, but these situations are uncommon. The main diagnostic challenge is to promptly and correctly identify lesions that require surgical repair. Diagnostic delay exceeding eight hours before surgical repair is associated with increased morbidity and probably with mortality. Because of this risk, the traditional therapeutic approach has been to operate on all patients with suspected bowel or mesenteric injury. However, this approach leads to a high rate of non-therapeutic laparotomy. A new approach of non-operative management (NOM) may be applicable to hemodynamically stable patients with no signs of perforation or peritonitis, and is being increasingly employed. This attitude has been described in several recent studies, and can be applied to nearly 40% of patients. However, there is no consensual agreement on which criteria or combination of clinical and radiological signs can insure the safety of NOM. When NOM is decided upon at the outset, very close monitoring is mandatory with repeated clinical examinations and interval computerized tomography (CT). Larger multicenter studies are needed to better define the selection criteria and modalities for NOM.

An anatomic and morphometric analysis of splenic variability using 3D reconstruction and spatial orientation from computed tomography

INTRODUCTION

In terms of frequency, the spleen is the first organ affected in abdominal trauma, resulting even today in a high rate of mortality (10%). Nevertheless, very few studies have investigated splenic quantitative morphometry as to shape and spatial orientation. Therefore, we analysed healthy spleen variability in order to integrate it in its environment and to correlate its morphometric parameters to anthropometric characteristics.

METHODS

Ninety abdominopelvic CT-scans performed on patients over 16 years with no splenic pathology were retrospectively selected among a Mediterranean population. Three age groups ([16-30], [30-60] and [over 60 years]), equally distributed among genders, were created. Parameters, such as volume, characteristic checkpoints, orientation, and morphology, were measured on the spleen, the 11th thoracic vertebra and the 10th ribs in three-dimensional reconstructions. Anthropometric parameters were characterised by waist circumference, costo-xiphoid angle, abdominal height and chest depth.

RESULTS

Observed variations in splenic morphology were divided into three groups: cupped (66.7%), coiled (17.8%), and flat (15.5%). Splenic morphometry tends to be abdominal-shaped (54.5%) or dorsal-shaped (45.5%). The mean of the angle between the main axis of the spleen and the CT-scan horizontal axis was 40±14°. Correlations were highlighted between volume and gender (p<0.05), splenic morphology and liver morphometry (p<0.05) as well as between orientation of hilar surface and splenic morphometry (p<0.01). Moreover, the spleen is more horizontal in women (p<0.05), in the elderly (p<0.05) and in the obese (p<0.01).

CONCLUSION

This study defines three groups based on shape and highlights correlations between parameters describing healthy splenic variability and its anthropometric characteristics, which are of great importance for numerical modelling in splenic studies.

[Effects of artificial shrinkage prior to vitrification in a closed system: a randomized controlled trial]

OBJECTIVE

To evaluate the effect of induced blastocoele shrinkage before vitrification in a closed carrier device.

PATIENTS AND METHODS

Prior to vitrification, blastocyst cavity was artificially shrinked by laser pulse or not treated according to a 2:1 randomized procedure. A total of 185 warming cycles from April 2011 to March 2013 have been analyzed. Clinical pregnancy rate and survival rate were compared between the two groups. The mean (±SD) women age was 33.5±5.7 years for both groups.

RESULTS

The pregnancy rate in the group with artificial reduction of the cavity was higher ([32/67] 47.7%) than in the control group but not significantly ([43/113] 38%). The survival rate in the artificial shrinkage group was significantly higher compared with the control group : 99% (102/103) and 91.8% (168/183) respectively (P=0.01).

DISCUSSION AND CONCLUSION

This study reveals that artificial shrinkage of blastocoelic cavity by laser pulse before vitrification in a closed carrier device improves survival rate after warming.

Response of the seagrass Posidonia oceanica to different light environments: Insights from a combined molecular and photo-physiological study

Here we investigated mechanisms underlying the acclimation to light in the marine angiosperm Posidonia oceanica, along its bathymetric distribution (at -5 m and -25 m), combining molecular and photo-physiological approaches. Analyses were performed during two seasons, summer and autumn, in a meadow located in the Island of Ischia (Gulf of Naples, Italy), where a genetic distinction between plants growing above and below the summer thermocline was previously revealed. At molecular level, analyses carried out using cDNA-microarray and RT-qPCR, revealed the up-regulation of genes involved in photoacclimation (RuBisCO, ferredoxin, chlorophyll binding proteins), and photoprotection (antioxidant enzymes, xanthophyll-cycle related genes, tocopherol biosynthesis) in the upper stand of the meadow, indicating that shallow plants are under stressful light conditions. However, the lack of photo-damage, indicates the successful activation of defense mechanisms. This conclusion is also supported by several responses at physiological level as the lower antenna size, the higher number of reaction centers and the higher xanthophyll cycle pigment pool, which are common plant responses to high-light adaptation/acclimation. Deep plants, despite the lower available light, seem to be not light-limited, thanks to some shade-adaptation strategies (e.g. higher antenna size, lower Ek values). Furthermore, also at the molecular level there were no signs of stress response, indicating that, although the lower energy available, low-light environments are more favorable for P. oceanica growth. Globally, results of whole transcriptome analysis displayed two distinct gene expression signatures related to depth distribution, reflecting the different light-adaptation strategies adopted by P. oceanica along the depth gradient. This observation, also taking into account the genetic disjunction of clones along the bathymetry, might have important implications for micro-evolutionary processes happening at meadow scale. Further investigations in controlled conditions must be performed to respond to these questions.

[Oncofertility program at the Montpellier university hospital 2 years after]

OBJECTIVE

Female fertility preservation in the context of cancer management is crucial for patient's health care. The aim of this study was to evaluate the oncofertility practice at our university hospital of Montpellier since 2011.

PATIENTS AND METHODS

The evaluation of management of young patients referred to Montpellier University Hospital from September 2011 to September 2013 for oncofertility counselling before cancer treatment.

RESULTS

Seventy-one patients were referred to a specialized oncofertility center. Forty-two patients (59.1%) were included in the oncofertility program. Twenty-two patients (31%) were proposed for oocyte vitrification after COS protocol, eight patients (11.3%) for ovarian tissue cryoconservation, seven patients (9.9%) for GnRH injections, three patients (4.2%) ovarian transposition and two patients (2.8%) for embryo cryopreservation. Among the 42 indications of fertility preservation, only 18 will have finally taken place.

CONCLUSION

Oncofertility counselling for young patients should now be part of the cancer management. It involves multidisciplinary teams. Further information of both oncologists and patients is needed to improve this new approach in the field of cancer treatments.

Blunt bowel and mesenteric injuries detected on CT scan: who is really eligible for surgery?

BACKGROUND

There is no consensually accepted approach to the management of blunt bowel and mesenteric injuries. Surgery is required urgently in the case of bowel perforation or haemodynamic instability, but several patients can be treated non-operatively. This study aimed to identify the risk factors for surgery in an initial assessment.

METHODS

We retrospectively reviewed the medical charts and computed tomography (CT) scans of adult patients presenting with a blunt abdominal trauma to our centre between the years 2004 and 2011. We included only patients with a CT scan showing suspected injury to the mesentery or bowel.

RESULTS

There were 43 patients (33 males and 10 females), with a mean Injury Severity Score (ISS) of 22. The most frequently suspected injuries based on a CT scan were mesenteric infiltrations in 40 (93 %) patients and bowel wall thickening in 22 (51 %) patients. Surgical therapy was required for 23 (54 %) patients. Four factors were independently associated with surgical treatment: a free-fluid peritoneal effusion without solid organ injury [adjusted odds ratio (OR) = 14.4, 95 % confidence interval (CI) [1.9-111]; p = 0.015], a beaded appearance of the mesenteric vessels (OR = 9 [1.3-63]; p = 0.027), female gender (OR = 14.2 [1.3-159]; p = 0.031) and ISS >15 (OR = 6.9 [1.1-44]; p = 0.041). Surgery was prescribed immediately for 11 (26 %) patients and with delay, after the failure of initially conservative treatment, for 12 (28 %) patients. The presence of a free-fluid peritoneal effusion without solid organ injury was also an independent risk factor for delayed surgery (OR = 9.8 [1-95]; p = 0.048).

CONCLUSIONS

In blunt abdominal trauma, the association of a bowel and/or mesenteric injury with a peritoneal effusion without solid organ injury on an initial CT scan should raise the suspicion of an injury requiring surgical treatment. Additionally, this finding should lead to a clinical discussion of the benefit of explorative laparotomy to prevent delayed surgery. However, these findings need validation by larger studies.

Posterior urethral injuries associated with motorcycle accidents and pelvic trauma in adolescents: analysis of urethral lesions occurring prior to a bony fracture using a computerized finite-element model

Adolescent males involved in motorcycle accidents are particularly at risk for pelvic injury, which may provoke a posterior urethral injury. The aim of this study was to develop a model to analyze the association between injuries and fractures of the pelvic ring and the risk of posterior urethral injury.

METHOD

Based on experience with traffic accident modeling, a computerized finite-element model was extrapolated from a computerized tomography scan of a 15-year-old boy. The anatomic structures concerned in urethral and pelvic ring trauma were isolated, rendered in 3D and given biomechanical properties. The model was verified according to available experiments on pelvic ring trauma.

RESULTS

To apply the model, we recreated three impact mechanisms on the pelvic ring: lateral impact, antero-posterior impact and a real car‒motorcycle accident situation (postero-lateral impact). In all three situations, stretching of the posterior urethra was identified prior to bony fracture visualization.

CONCLUSION

Application of this model allowed us to analyze precisely the link between trauma of the pelvic ring and lesions of the posterior urethra. The results should help to establish guidelines for urethral catheterization in male adolescents in cases of pelvic trauma, even when no bony fracture is present, in order to prevent iatrogenic worsening of a misdiagnosed posterior urethral trauma.

Establishing research strategies, methodologies and technologies to link genomics and proteomics to seagrass productivity, community metabolism, and ecosystem carbon fluxes

A complete understanding of the mechanistic basis of marine ecosystem functioning is only possible through integrative and interdisciplinary research. This enables the prediction of change and possibly the mitigation of the consequences of anthropogenic impacts. One major aim of the European Cooperation in Science and Technology (COST) Action ES0609 "Seagrasses productivity. From genes to ecosystem management," is the calibration and synthesis of various methods and the development of innovative techniques and protocols for studying seagrass ecosystems. During 10 days, 20 researchers representing a range of disciplines (molecular biology, physiology, botany, ecology, oceanography, and underwater acoustics) gathered at The Station de Recherches Sous-marines et Océanographiques (STARESO, Corsica) to study together the nearby Posidonia oceanica meadow. STARESO is located in an oligotrophic area classified as "pristine site" where environmental disturbances caused by anthropogenic pressure are exceptionally low. The healthy P. oceanica meadow, which grows in front of the research station, colonizes the sea bottom from the surface to 37 m depth. During the study, genomic and proteomic approaches were integrated with ecophysiological and physical approaches with the aim of understanding changes in seagrass productivity and metabolism at different depths and along daily cycles. In this paper we report details on the approaches utilized and we forecast the potential of the data that will come from this synergistic approach not only for P. oceanica but for seagrasses in general.

Effectiveness and safety of saquinavir/ritonavir in HIV-infected pregnant women: INEMA cohort

OBJECTIVE

The authors had for aim to describe the effectiveness and the safety of a saquinavir/ritonavir (SQV/r) regimen, 1000/100mg twice daily, in HIV-infected pregnant patients.

PATIENTS AND METHOD

We made a prospective and observational study of HIV positive female patients beginning or going on SQV/r antiretroviral treatment (ART) during pregnancy.

RESULTS

Sixty-two patients were enrolled from July 2007 to June 2009 in 10 infectious diseases units in France. Thirty-six women (group 1) were ART naive on inclusion, 20 (group 2) had been previously treated and then switched to SQV/r, six (group 3) were treated with SQV/r before pregnancy. 58 patients delivered while on SQV/r regimen after a median pregnancy duration of 39 WA. Eighty percent had a viral load below 50 copies/mL and 93% below 400 copies/mL: respectively 77% and 93.5% in group 1, 83% and 89% in group 2, 83% and 100% in group 3. The median SQV minimum concentrations (C(min)) measured at the third trimester and at delivery were adequate, respectively 0.91 mg/L and 0.86 mg/L. Most women (52%) had a vaginal delivery; 12 (21%) had an elective caesarean section, for obstetrics factors in eight cases. None of the newborns were HIV-infected at 6 months of age (n = 59, one death at day 3). Only one severe adverse event occurred due to saquinavir (maternal grade 3 hepatotoxicity).

CONCLUSION

SQV/r 1000/100mg twice daily seems to be effective and safe in HIV-infected pregnant women with adequate saquinavir C(min).

Dual-modulation fiber Fabry-Perot interferometer with double reflection for slowly-varying displacements

This Letter describes a dual-amplitude modulation technique incorporated into a double reflection extrinsic-type fiber Fabry-Perot interferometer to measure periodic, nonperiodic as well as quasi-static displacements. The modulation scheme simultaneously maintains the interference signal pair in quadrature and provides a reference signal for displacements inferior to a quarter of the source wavelength. The control and phase demodulation of the interferometer carried out via software enable quasi-real-time measurement and facilitates sensor alignment. The sensor system can be exploited in the low frequency range from 10(-3) to ∼500 Hz and has a resolution better than 2.2 nm, targeting applications in geophysics.

Synthesis and Spectroscopic Characterization of Diphenylargentate, [(C6H5)2Ag](.)

We present the structural and optical properties of the isolated diphenylargentate anion, which has been synthesized by multistage mass spectrometry in a quadrupole ion trap. The experimental photodetachment spectrum has been obtained by action spectroscopy. Comparison with quantum chemical calculations of the electronic absorption spectrum allows for a precise characterization of the spectroscopic features, showing that in the low-energy regime, the optical properties of diphenylargentate bear a significant resemblance to those of atomic silver.

Posterior urethral injuries associated with pelvic injuries in young adults: computerized finite element model creation and application to improve knowledge and prevention of these lesions

INTRODUCTION

Young adult males involved in motorcycle accidents are particularly at risk for posterior urethral injury whenever pelvic injury occurs. Posterior urethral injuries remain problematic because their diagnosis may be missed, and during the initial treatment response the urethral injury can be aggravated by urethral catheterization. Few anatomical and clinical tools exist that establish a correlation between injuries and fractures of the pelvic ring and the risk of posterior urethral injury.

METHOD

Based on experience with traffic accident modeling, a computerized finite element model was conceived integrating the specific anatomic structures concerned. This model was extrapolated from a CAT scan of a young adult. The anatomic structures concerned in urethral and pelvic ring trauma (PRT) were isolated, placed in 3D and given biomechanical properties. The model was verified according to available experiments on PRT.

RESULTS

To apply the model, we recreated a lateral impact mechanism on the pelvic ring. Stretching between the prostatic and membranous portions of the urethra (before and after visualization of a pelvic fracture) as well as timing of injury was studied.

CONCLUSION

The model's application permitted us to analyze precisely the link between lateral impact trauma of the pelvic ring and lesions of the posterior urethra and to identify an urethra stretching prior to visualization of a pelvic fracture. Utilization of the model with other mechanisms of injury should allow for better comprehension of this associated trauma, improved prevention, iatrogenic aggravation of, and care for, these serious injuries.

Binary mixture adsorbed in a slit pore: Field-induced population inversion near the bulk instability

The recently proposed method for modulating through an external field the composition of a binary fluid mixture adsorbed in a slit pore is discussed. The population inversion near the bulk (demixing) instability is first analyzed in the case of a symmetric mixture of nonadditive hard spheres, without field. It is next investigated for a mixture comprising dipolar particles subject to an external field. The influence of several factors on the adsorption curves including bulk composition, pore width, field direction, polarizability versus permanent dipoles, and temperature on this field induced population inversion is shown by Monte Carlo simulation.

[Experimental research on mechanical behavior of human placenta]

OBJECTIVES

Determination of mechanical properties of human placenta.

PATIENTS AND METHODS

Realisation of an experimental study using 80 human placentas and modelisation of this study using a finite element numerical model. Using the inverse analysis method, research of the parameters of placenta's behavior.

RESULTS

Hyper-Visco-Elastic law written by Ogden, optimized for placenta with parameters: mu(1)=0.0001881Mpa, mu(2)=-0.000240Mpa, mu(3)=mu(4)=0Mpa and alpha(1)=2, alpha(2)=-8, alpha(3)=alpha(4)=0 in static condition.

DISCUSSION AND CONCLUSION

The parameters enable an approach of the mechanical behavior of the placenta. They could be used in numerical modelisation.

[Risks related to tobacco use in general and intestinal surgery]

Peri-operative smoking history is an important risk factor, which is often under-appreciated by surgeons. In the first place, tobacco use predisposes patients to specific pathologies, which may require surgical intervention. Secondarily, smoking has been shown to increase surgical risks of mortality, morbidity and length of hospital stay. Of particular importance in general surgery is the increased risk of anastomotic leak with fistula formation, of deep infections, and of abdominal wall complications (infection and ventral hernia). If the patient can stop smoking prior to surgery, there is a concomitant decrease in post-operative complications. Surgeons should be familiar with the pharmacologic and behavioral interventions, which may help the patient with smoking cessation and should not hesitate to defer elective surgery for four to eight weeks so that the patient may have the full benefit of smoking cessation.

Pharmacoeconomic study in head and neck cancer patients: Impact of prospective DPD deficiency screening with 5-fluorouracil (5-FU) dose tailoring on toxicities-related costs

6515

Background: Dihydropyrimidine dehydrogenase (DPD) plays a pivotal role in the detoxification of 5-FU. We studied the impact of screening DPD impairment in head and neck cancer (HNC) patients, both on reduction of drug-related toxicities and as a pharmacoeconomic endpoint. Methods: A total of 148 consecutive patients with HNC treated with 5-FU+platinum were monitored. Seventy-four patients (Arm A - before 2006) were treated with standard dosage, whereas 74 other patients (Arm B - after 2006) had their DPD status phenotypically evaluated prior to receiving 5-FU, with subsequent dose reduction if DPD deficiency were suspected. Severe toxicities and response were compared. Additionally, direct and indirect costs required to manage the treatment-related toxicities and to establish DPD status were calculated. Results: Sepsis was observed in 16.2% of patients treated with standard dosage. In Arm B, DPD deficiency was suspected in 35% of the patients and 5-FU dosage was subsequently reduced. Consequently, only 1.8% of them experienced sepsis. Of note, response rates were comparable between Arm A and B (62 vs 61%, p>0.05), thus demonstrating that 5-FU dose tailoring did not negatively impact on treatment efficacy, while reducing the occurrence of severe toxicities. Managing toxicities required an average 23-days of extra-hospitalization (4–96 days), including an average 1.6-day stay in ICU. No patients from Arm B had to stay in ICU. Drugs required for managing toxicities cost an average of $339 per patient (Arm A) and was reduced down to $38 per patient (Arm B). Similarly, mean extra-hospitalization cost was $5,940/patient in Arm A and $245/patient in Arm B. Testing DPD cost $49/patient in Arm B. Conclusions: Developing an adaptative dosing strategy based upon DPD status evaluation led to a dramatic reduction of the incidence of 5-FU-related severe toxicities, while maintaining optimal efficacy. Subsequently, extra-cost (medication + hospitalization costs) required to manage the toxicities fell down from $6,279 to $294/patient. Overall, this study advocates that systematic screening for DPD deficiency could be cost-efficient in the setting of 5-FU-based chemotherapies, with a reduction of 95% of the extra-costs.

No significant financial relationships to disclose.